Screening device for wet screening of paper fiber suspension has screen plate pre-stressed to exert compressive forces on middle support ring, and tensile forces on both inner and outer support rings

摘要

A detachable support structure (3) is attached to a screen plate (1) and consists of an outer support ring (6) and an inner support ring (4). At least one middle support ring (5) is arranged radially between the inner and outer support rings to support the screen plate. A rotor is movable adjacent the screen plate. An outlet opening (18) is provided for passing a portion of a paper fiber suspension through screen openings (2). The screen plate is pre-stressed to exert compressive forces on the middle support ring, and tensile forces on both the inner and outer support rings.